LAS VEGAS--When CNET reviewed Polk's I-Sonic ES2 almost four years (!) ago, we knocked it for lacking then-cutting-edge features like a CD/DVD player, satellite radio, USB port, and network audio functionality.

Fast-forward to 2012 and the story is the same, but the details have changed, with Polk's recently announced I-Sonic ES3 lacking many of the cutting-edge features we've seen on competing iPhone speakers, such as AirPlay and Bluetooth. Even the USB-looking port on the back, but close inspection reveals it's for service-use only.

Back panel.
Polk

Still, the I-Sonic's real claim-to-fame was always performance, not features, which is why it's always garnered solid reviews from CNET. The first two I-Sonic tabletop radios sounded better than pretty much anything else that size, especially when it came to bass. And it's worth pointing out that the the I-Sonic ES3 is designed to be used an alarm clock (with a proper snooze button), which is something lacking from many other iPhone speakers.

The Polk I-Sonic ES3 will be released in the spring with a list price of $300. With a premium price tag and a dearth of features, the Polk I-Sonic will need some serious performance to woo digital audiophiles.